Micromechanics based modeling of Dual Phase steels: Prediction of ductility and failure modes

A micromechanics based approach by means of representative volume element (RVE) is employed to predict the flow behavior, plastic strain localization and plastic instability of Dual Phase (DP) steels. Boundary condition of 2D RVE during uniaxial tensile loading depends upon its position on tensile specimen. The ductile failure of DP steels under uniaxial tensile loading with different boundary conditions is predicted in the form of plastic strain localization without any prescribed damage/failure criteria for the individual phases. This indicates that the microstructure level inhomogeneity of the various constituent phases can be the key factor influencing the final ductility of the DP steels under different loading conditions. Comparisons of the computational results with experimental data available from literature suggest that the microstructure based modeling approach captures the overall macroscopic behavior of DP steels under different loading and boundary conditions.